WO2001070640A1 - Guides d'ondes optiques et dispositifs incorporant lesdits guides d'ondes - Google Patents

Guides d'ondes optiques et dispositifs incorporant lesdits guides d'ondes Download PDF

Info

Publication number
WO2001070640A1
WO2001070640A1 PCT/GB2001/001218 GB0101218W WO0170640A1 WO 2001070640 A1 WO2001070640 A1 WO 2001070640A1 GB 0101218 W GB0101218 W GB 0101218W WO 0170640 A1 WO0170640 A1 WO 0170640A1
Authority
WO
WIPO (PCT)
Prior art keywords
glass
photosensitive glass
group
refractive index
optical
Prior art date
Application number
PCT/GB2001/001218
Other languages
English (en)
Inventor
Gilberto Brambilla
Valerio Pruneri
Laurence Reekie
Original Assignee
University Of Southampton
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University Of Southampton filed Critical University Of Southampton
Priority to AT01911990T priority Critical patent/ATE286492T1/de
Priority to DE60108228T priority patent/DE60108228T2/de
Priority to EP01911990A priority patent/EP1265820B1/fr
Priority to AU40908/01A priority patent/AU4090801A/en
Publication of WO2001070640A1 publication Critical patent/WO2001070640A1/fr
Priority to US10/241,615 priority patent/US6643442B2/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/0632—Thin film lasers in which light propagates in the plane of the thin film
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C13/00—Fibre or filament compositions
    • C03C13/04—Fibre optics, e.g. core and clad fibre compositions
    • C03C13/045—Silica-containing oxide glass compositions
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C13/00—Fibre or filament compositions
    • C03C13/04—Fibre optics, e.g. core and clad fibre compositions
    • C03C13/045—Silica-containing oxide glass compositions
    • C03C13/046—Multicomponent glass compositions
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C3/00—Glass compositions
    • C03C3/04—Glass compositions containing silica
    • C03C3/06—Glass compositions containing silica with more than 90% silica by weight, e.g. quartz
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C3/00—Glass compositions
    • C03C3/04—Glass compositions containing silica
    • C03C3/076—Glass compositions containing silica with 40% to 90% silica, by weight
    • C03C3/078—Glass compositions containing silica with 40% to 90% silica, by weight containing an oxide of a divalent metal, e.g. an oxide of zinc
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C3/00—Glass compositions
    • C03C3/04—Glass compositions containing silica
    • C03C3/076—Glass compositions containing silica with 40% to 90% silica, by weight
    • C03C3/095—Glass compositions containing silica with 40% to 90% silica, by weight containing rare earths
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C4/00—Compositions for glass with special properties
    • C03C4/04—Compositions for glass with special properties for photosensitive glass
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/02—Optical fibres with cladding with or without a coating
    • G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
    • G02B6/02076—Refractive index modulation gratings, e.g. Bragg gratings
    • G02B6/02114—Refractive index modulation gratings, e.g. Bragg gratings characterised by enhanced photosensitivity characteristics of the fibre, e.g. hydrogen loading, heat treatment
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B6/122—Basic optical elements, e.g. light-guiding paths
    • G02B6/124—Geodesic lenses or integrated gratings
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B6/13—Integrated optical circuits characterised by the manufacturing method
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2201/00—Glass compositions
    • C03C2201/06—Doped silica-based glasses
    • C03C2201/30—Doped silica-based glasses containing metals
    • C03C2201/40—Doped silica-based glasses containing metals containing transition metals other than rare earth metals, e.g. Zr, Nb, Ta or Zn
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C2201/00—Glass compositions
    • C03C2201/06—Doped silica-based glasses
    • C03C2201/30—Doped silica-based glasses containing metals
    • C03C2201/50—Doped silica-based glasses containing metals containing alkali metals
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/02—Optical fibres with cladding with or without a coating
    • G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
    • G02B6/02076—Refractive index modulation gratings, e.g. Bragg gratings
    • G02B6/02123—Refractive index modulation gratings, e.g. Bragg gratings characterised by the method of manufacture of the grating
    • G02B2006/02161—Grating written by radiation passing through the protective fibre coating
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/067—Fibre lasers
    • H01S3/06708—Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/067—Fibre lasers
    • H01S3/0675—Resonators including a grating structure, e.g. distributed Bragg reflectors [DBR] or distributed feedback [DFB] fibre lasers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/1601—Solid materials characterised by an active (lasing) ion
    • H01S3/1603—Solid materials characterised by an active (lasing) ion rare earth
    • H01S3/1608—Solid materials characterised by an active (lasing) ion rare earth erbium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/1601—Solid materials characterised by an active (lasing) ion
    • H01S3/1603—Solid materials characterised by an active (lasing) ion rare earth
    • H01S3/1611—Solid materials characterised by an active (lasing) ion rare earth neodymium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/1601—Solid materials characterised by an active (lasing) ion
    • H01S3/1603—Solid materials characterised by an active (lasing) ion rare earth
    • H01S3/1618—Solid materials characterised by an active (lasing) ion rare earth ytterbium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/163—Solid materials characterised by a crystal matrix
    • H01S3/1655—Solid materials characterised by a crystal matrix silicate

Definitions

  • the invention relates to optical waveguides comprising photosensitive glass, and to optical waveguide devices containing such glass, such as optical fibre gratings, optical fibre dispersion compensators, optical fibre sensors, optical fibre lasers and planar waveguide devices.
  • Photosensitivity of glass materials is a fundamental property for the realisation of many optical devices.
  • Typical glasses used for these applications are photosensitive to ultraviolet (UV) light.
  • UV ultraviolet
  • Bragg gratings in optical fibres and planar waveguides have attracted much attention since their first demonstration.
  • Bragg gratings are obtained by exposure of a waveguide made of photosensitive glass to a periodic light pattern.
  • Such devices have many applications, such as sensors, dispersion compensators and laser mirrors.
  • channel waveguides using UV writing on glass substrates such as silica on silicon
  • silica on silicon is also becoming increasingly important for the realisation of multifunctional integrated optical components.
  • Telecommunications optical fibres i.e. Si0 fibres with a low content of Ge0 2 ( ⁇ 3%), show only relatively small refractive index changes when exposed to UV radiation.
  • the UV photoinduced index change in standard germanosilicate waveguides is not sufficient for writing complex structures with a high degree of integration.
  • photosensitive glasses it is thus necessary to increase the photosensitivity of optical fibres or planar waveguides through post-fabrication methods and co-doping.
  • Typical post-fabrication methods are hydrogen/deuterium loading and flame brushing.
  • Typical co-dopants are B 2 0 , Sn0 2 and rare earth elements.
  • Sn0 2 is used mainly as a codopant in germanosilicate, phosphosilicate and aluminosilicate glasses [see references 1,2,3,4].
  • Optical fibre with numerical apertures (NA) between 0.23 and 0.29 and refractive index modulations of ⁇ 10° can be produced in this way.
  • Sn0 2 doped or co-doped fibre via modified chemical vapour deposition (MCVD) or solution doping techniques is related to the high volatility of Sn0 2 at the temperature required for preform collapse. This problem effectively prevents high Sn0 concentrations being incorporated into a fibre. An analogous problem can be expected to arise for other glass preparation processes.
  • MCVD modified chemical vapour deposition
  • solution doping techniques are related to the high volatility of Sn0 2 at the temperature required for preform collapse. This problem effectively prevents high Sn0 concentrations being incorporated into a fibre.
  • An analogous problem can be expected to arise for other glass preparation processes.
  • a Group I element such as sodium in a tin-doped silica glass matrix provides a glass with highly desirable properties for use in waveguides, either made from optical fibres with the glass forming the core, or as part of a planar waveguide structure.
  • the invention provides an optical waveguide having a waveguiding channel of photosensitive glass with a modified refractive index optically written therein, wherein the photosensitive glass comprises an oxide of sodium or another Group I element such as lithium or potassium in a matrix of silicon and tin oxides.
  • the optical waveguide may be an optical fibre, with the waveguiding channel being formed by a core of the optical fibre comprising the photosensitive glass.
  • the optical waveguide may also be a planar waveguide device comprising a layer of the photosensitive glass with a waveguiding channel optically written into the layer. Integrated planar waveguide structures may thus be fabricated by writing a channel network into the photosensitive glass layer.
  • the glass comprises the oxides Si0 , Sn0 2 and Na 0.
  • the inclusion of sodium oxide with silica and tin oxide has been shown to produce a photosensitive glass with a highly desirable combination of properties.
  • a further advantage of inclusion of Na is that the effects related to high volatility of Sn during preform collapse are reduced.
  • Si0 2 :Sn0 :Na 2 0 glass have been shown to have remarkable temperature stability, much superior to conventional Si0 2 :Ge0 glasses. It has been shown that the temperature stability is at least as good as that of the binary photosensitive glass Si0 2 :Sn0 2 .
  • Sodium oxide incorporation can thus be used to increase Sn concentration to increase intrinsic photosensitivity, while simultaneously providing a glass in which optically written refractive index modulations are highly stable.
  • the photosensitive glass may comprise at least one of:
  • tin and Group I oxides can be applied not only to pure silica glass, but also to silica doped with other elements, e.g. to germanosilicate glass, phosphosilicate glass or aluminosilicate glass, or combinations thereof. Additional rare earth dopants such as Er, Nd or Yb may also be included to provide gain. References to silica glass and a silica matrix are therefore to be construed as covering silica doped with other elements such as germanium, phosphorous or aluminium. Similarly references to a ternary compound are to be construed as inclusive of quaternary and higher order compounds.
  • the photosensitive glass may be used for many device applications.
  • an optical fibre can be provided that has a core made of the photosensitive glass.
  • a planar waveguide comprising the photosensitive glass can also be provided.
  • an optical device having a gain medium comprising the photosensitive glass for example a laser, optical amplifier or light emitter.
  • suitable dopants such as the rare earth elements Er, Nd, Yb may be included.
  • a grating structure may be written into the photosensitive glass, as is described further below in the specific description.
  • devices made of the glass are more robust to intrinsic absorption, multi-photon absorption, high temperatures and other related effects which all tend to erase optically-written refractive index modulations.
  • the glass is especially attractive for applications such as high power lasers and amplifiers where residual absorption effects or multiphoton absorption are typically large and where significant temperature increases may arise during operation.
  • the refractive index modulations can withstand such high operating temperatures, devices incorporating the glass can be run hotter and at higher intensities. In this way cooling requirements are less stringent and devices can be run at higher output levels.
  • the high temperature stability is indicative of a high characteristic activation energy for the photoinduced refractive index changes, which are thought to originate from electron trapping effects. Consequently, even if device operating temperatures are kept low by cooling or pulsed operation, high power devices incorporating a modulated refractive index profile optically written into the glass are expected to demonstrate enhanced stability. For example, device reliability and operating life are expected to be improved.
  • an optical waveguide device comprising: an optical waveguide formed at least in part of photosensitive glass, wherein the photosensitive glass is doped with tin as a photosensitising dopant; and a refractive index variation optically impressed on the photosensitive glass of the optical waveguide; wherein the photosensitive glass is doped additionally with a Group I element as a dopant for increasing solubility of tin in the glass.
  • a method of fabricating an optical waveguide comprising: providing a photosensitive glass doped with tin as a photosensitising dopant and a Group I element as a dopant for increasing solubility of tin in the photosensitive glass; and exposing regions of the photosensitive glass to refractive index change inducing optical radiation, the exposed regions providing a light-guiding core of raised refractive index within the photosensitive glass.
  • a process for increasing the sensitivity of optical glass to light-induced refractive index variations comprising: doping the optical glass with tin as a photosensitising dopant in combination with a Group I element as a further dopant for incorporating increased amounts of tin in the optical glass, thereby to increase the sensitivity of the optical glass to light induced refractive index variation; and exposing regions of the optical glass to varying optical radiation to modulate the refractive index of the optical glass.
  • Figure 1 shows refractive index modulation as a function of exposure time
  • Figure 2 shows the initial speed of refractive index modulation growth as a function of UV laser intensity in a glass according to an embodiment of the invention
  • Figure 3A shows temperature stability for gratings written in a glass according to an embodiment of the invention, and three further glasses, in terms of degradation of the amplitude of the gratings' refractive index modulation as temperature is increased;
  • Figure 3B shows temperature stability for the grating according to the embodiment of the invention shown in Figure 3 A in terms of reflection response as temperature is increased;
  • Figure 5 shows a schematic cross-section of an optical fibre with a core of photosensitive glass in which has been written a refractive index modulation
  • Figure 6 shows in elevation a planar waveguide structure optically written onto the surface of an epitaxial or bulk layer of photosensitive glass
  • Figure 7 shows in elevation a planar waveguide structure optically written into a layer of photosensitive glass sandwiched between a buffer layer and cap layer;
  • Figure 8 shows an optical fibre laser with Bragg reflector cavity mirrors;
  • Figure 9 shows a chirped grating;
  • Figure 10 shows an optical fibre sensor.
  • An optical fibre was produced by collapsing a Suprasil (TM) cladding onto a small cylindrical glass core rod while pulling.
  • the glass was then cast and drilled with an ultrasonic drill.
  • the cylinder 1.5 mm diameter and 50 mm height
  • HF hydrofluoric acid
  • a grating for reflectivity at -1.55 ⁇ m was written in the fibre using a pulsed KrF excimer laser (wavelength 248 nm) working at 30 Hz and a phase mask. Pulse duration and fluence were estimated to be 20 ns and 140 mJ/pulse*cm 2 . The grating length was approximately 2 mm.
  • Figure 1 shows the increase of the refractive index modulation with exposure time in minutes. A saturation level is reached at 6.2* 10 " after 120 minutes exposure. Measurements at different intensities have been performed in order to understand whether the photosensitivity of this sample is driven by a one or two-photon absorption process.
  • Figure 2 shows the initial growth of the refractive index modulation as a function of laser intensity, which appears linear and has a gradient of 1.1. This is evidence that the photorefractive effect of the glass is based on a one-photon process.
  • Figure 3A shows the results of temperature stability studies made on gratings written into photosensitive glass of four different composition types. The plot is of the amplitude of the refractive index modulation against temperature in degrees
  • the refractive index modulation at the temperature concerned is normalised to the initial refractive index modulation at 20 °C before heating.
  • the refractive index modulation was measured in each case during step heating.
  • the samples were heated first to 205 °C and then to higher temperatures in steps of about 45 °C.
  • Each temperature ramp took about 2 minutes and was followed by keeping the sample at a constant temperature for about 28 minutes, before increasing the temperature again with another step.
  • the four examples are gratings written in the Na 2 0:Sn0 2 :Si0 2 glass (SSN2 - filled circles), in comparison to gratings written in the SiO?: Sn0 2 glasses of reference [5] (SS - open circles), and those written in germanosilicate glass Si0 :Ge0 (SG - filled triangles) and borogermanosilicate glass Si0 :Ge0 :B 2 ⁇ 3 (SGB - open triangles).
  • the enhanced stability of the gratings written into Sn0 2 :Si0 2 and Na 2 O:Sn0 2 :Si0 as compared to germanosilicate and borogermanosilicate is striking.
  • Figure 3B shows the reflection response of the grating written into the
  • the response curves being measured at points shown in Figure 3A.
  • the response curves were taken at: 20 (A) , 205 (B), 343 (C), 484 (D), 580 (E), 681 (F), 767 (G), 852 (H), 895 (I) and 940 °C (J), the peak response wavelength increasing gradually from around 1546 nm.
  • the grating was stable up to and including the 681 °C measurement (response F at 1552 nm), with the first degradation being discernible at 767 °C (response G).
  • Fig. 4 is taken from reference [10] and shows the relation between the concentrations of the constituents in the ternary compounds Sn0 2 :Si0 2 :R 2 0 where R is Li (curve 1) Na (curve 2) or K (curve 3).
  • the curves represent the approximate concentration limits for crystallisation.
  • the maximum concentration of Sn0 2 for non-crystalline material is shown to be around 20 mol%. Inclusion of the Group I elements thus allows up to 20 times more Sn to be incorporated in a non-crystalline silica matrix.
  • the concentrations which can be achieved for the Group I elements range from minimum values of perhaps around 10 mol% to maximum values of about 40% for Li and 60% for Na and K.
  • a preferred concentration range is between about 10 and 60 mol%. It will be understood that this curves apply only for a pure silica matrix. Different curves will apply if, for example, a germanosilicate matrix is used. As described above, grating writing in ternary Si ⁇ 2 :Sn0 2 :Na 2 0 fibre, achieving significant refractive index modulation, has been demonstrated.
  • the fibre is produced using rod-in-tube techniques, rather than MCVD as in previous work. It is thought this may be helpful for achieving high Sn concentrations.
  • MCVD remains an option for low loss fibres where Sn solubility is increased by using Na via solution doping.
  • Figure 5 shows in axial cross-section an optical fibre according to the above- described embodiment.
  • the fibre comprises a core 20 of the photosensitive glass SnO 2 :Si ⁇ 2 :Na 2 0 in which is optically written a grating structure 25.
  • the core is surrounded by a clad 10.
  • Figure 6 shows a planar waveguide structure 25 optically written into a layer 20 of the photosensitive glass Sn0 2 :Si0 2 :Na 2 0 with a writing beam, or lithographically.
  • the photosensitive glass layer 20 is deposited on a silica substrate 5.
  • the waveguiding channel is written into the photosensitive glass layer 20 by focusing a light beam onto the surface of the layer.
  • Figure 7 shows a buried waveguide structure.
  • a silica buffer layer 12 is deposited on a silicon substrate 5.
  • a layer 22 of the photosensitive glass Sn0 2 :Si0 :Na 2 0 is deposited on the buffer layer 12 with a further silica capping layer 1 1 being deposited on the photosensitive glass layer 22.
  • a waveguiding channel 25 is written into the photosensitive glass layer 22 by focusing a light beam 23 so that the beam focus or waist is coincident with the layer 22.
  • FIG 8 is a schematic drawing of an optical fibre laser.
  • a laser cavity is defined by first and second Bragg gratings 30 and 40 optically written into an optical fibre with a core of the photosensitive glass Sn0 2 :Si0 2 :Na 2 0, as described with reference to Figure 5.
  • the gain medium 50 is also made of optical fibre, with the core being doped with Er or another suitable rare earth element such as Nd or Yb.
  • the entire structure may be of a single fibre type, e.g. with a core of Er-doped Sn0 2 :Si0 2 :Na 0 glass.
  • the photosensitive properties of the cavity core can then be utilised to fabricate a DFB (distributed feedback) laser.
  • DFB distributed feedback
  • the Bragg gratings may be written into fibre sections with a core of Sn ⁇ 2 :Si ⁇ 2 :Na 2 0, with a separate fibre section being provided for the cavity.
  • the cavity section will include a gain-inducing dopant such as a rare earth element, but need not include any photosensitising dopants.
  • a pump beam P is used to excite stimulated emission in the cavity to produce a laser output of wavelength ⁇ L .
  • Figure 9 shows a chirped fibre grating 60 with a core of the photosensitive glass Sn ⁇ 2 :Si ⁇ 2 :Na 2 ⁇ , as described with reference to Figure 5.
  • the chirped grating may be used as a dispersion compensator in long-haul fibre communication.
  • Figure 10 shows an optical fibre sensor.
  • the fibre comprises a core of the photosensitive glass Sn0 2 :Si ⁇ 2 :Na 2 ⁇ into which the gratings are optically written.
  • the circulator 72 is operable to route a probe light beam P from an input 70 through to the fibre section 80 and to route light reflected from the Bragg gratings to a further section of fibre 82 which leads to an output 77.
  • Light from the output 77 is detected by a photodetector 75 and analysed to determine from which of the Bragg gratings the light was reflected. Spectroscopic or time resolution techniques may be used for the analysis.
  • the device is used as a sensor by placing each of the Bragg gratings at different locations, each of which experiences a different physical environment. Pressure, temperature or strain may for example be measured in this way.
  • JP 80267676 A 'Soda lime-silica photosensitive glass and its production'.

Landscapes

  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Optics & Photonics (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electromagnetism (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Plasma & Fusion (AREA)
  • General Physics & Mathematics (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Glass Compositions (AREA)
  • Optical Integrated Circuits (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

L'invention concerne un verre photosensible constitué d'un composé ternaire SiO2:SnO2:R2O, où R représente un élément de Groupe I, notamment Na, K ou Li. L'addition d'un oxyde d'un élément du Groupe I, qui provoque l'augmentation de la solubilité de l'oxyde d'étain dans une matrice de silice, permet de produire un verre hautement photosensible, dans lequel les modulations de l'indice de réfraction écrites optiquement ont une stabilité thermique remarquable (cercles pleins), tout du moins aussi satisfaisante que celle du verre binaire SiO2:SnO2 (cercles vides) et nettement supérieure à celle du verre germanosilicate (triangles pleins) ou du verre borogermanosilicate (triangles vides) classique. L'inclusion de l'oxyde du Groupe I fait efficacement passer la solubilité de l'oxyde d'étain dans la matrice de silice non cristalline bien au-delà de la limite de 1 % du verre photosensible SiO2:SnO2, au niveau de laquelle le Sn se cristallise normalement dans l'oxyde. A la différence des co-dopants du type bore ou phosphore, l'introduction de l'élément du Groupe I ne semble pas provoquer une quelconque augmentation de l'indice de réfraction de fond, ce qui permet de fabriquer des guides d'ondes compatibles avec les fibres de télécommunication standard.
PCT/GB2001/001218 2000-03-23 2001-03-20 Guides d'ondes optiques et dispositifs incorporant lesdits guides d'ondes WO2001070640A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AT01911990T ATE286492T1 (de) 2000-03-23 2001-03-20 Optische wellenleiter und diese enthaltende vorrichtungen
DE60108228T DE60108228T2 (de) 2000-03-23 2001-03-20 Optische wellenleiter und diese enthaltende vorrichtungen
EP01911990A EP1265820B1 (fr) 2000-03-23 2001-03-20 Guides d'ondes optiques et dispositifs incorporant lesdits guides d'ondes
AU40908/01A AU4090801A (en) 2000-03-23 2001-03-20 Optical waveguides and devices including same
US10/241,615 US6643442B2 (en) 2000-03-23 2002-09-12 Optical waveguides and devices including same

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP00302381.9 2000-03-23
EP00302381 2000-03-23
US19530500P 2000-04-10 2000-04-10
US60/195,305 2000-04-10

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US10/241,615 Continuation US6643442B2 (en) 2000-03-23 2002-09-12 Optical waveguides and devices including same

Publications (1)

Publication Number Publication Date
WO2001070640A1 true WO2001070640A1 (fr) 2001-09-27

Family

ID=56290125

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2001/001218 WO2001070640A1 (fr) 2000-03-23 2001-03-20 Guides d'ondes optiques et dispositifs incorporant lesdits guides d'ondes

Country Status (5)

Country Link
EP (1) EP1265820B1 (fr)
AT (1) ATE286492T1 (fr)
AU (1) AU4090801A (fr)
DE (1) DE60108228T2 (fr)
WO (1) WO2001070640A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2850646A1 (fr) * 2003-02-03 2004-08-06 Schott Glas Corps photostructurable, procede pour le traitement d'un verre et/ou d'une vitroceramique, production de divers produits qui en sont derives, leur utilisation et objet utilisant ledit corps
CN112526671A (zh) * 2020-12-15 2021-03-19 新沂市锡沂高新材料产业技术研究院有限公司 一种低损耗的玻璃陶瓷平面光波导及其制备方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0826767A (ja) 1994-07-13 1996-01-30 Nippon Glass Kk ソーダ石灰シリカ系感光性ガラス及びその製造方法
WO1996034304A1 (fr) 1995-04-28 1996-10-31 University Of Southampton Dispositif pour guide d'ondes optique
US5698262A (en) 1996-05-06 1997-12-16 Libbey-Owens-Ford Co. Method for forming tin oxide coating on glass
WO1999018042A1 (fr) 1997-10-02 1999-04-15 Corning Incorporated Changements d'indice de refraction, induits par la lumiere, dans des verres basse temperature
US6009222A (en) * 1997-09-12 1999-12-28 Dong; Liang Optical fibre and optical fibre grating

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0826767A (ja) 1994-07-13 1996-01-30 Nippon Glass Kk ソーダ石灰シリカ系感光性ガラス及びその製造方法
WO1996034304A1 (fr) 1995-04-28 1996-10-31 University Of Southampton Dispositif pour guide d'ondes optique
US5698262A (en) 1996-05-06 1997-12-16 Libbey-Owens-Ford Co. Method for forming tin oxide coating on glass
US6009222A (en) * 1997-09-12 1999-12-28 Dong; Liang Optical fibre and optical fibre grating
WO1999018042A1 (fr) 1997-10-02 1999-04-15 Corning Incorporated Changements d'indice de refraction, induits par la lumiere, dans des verres basse temperature

Non-Patent Citations (8)

* Cited by examiner, † Cited by third party
Title
BANSAL & DOREMUS: "HANDBOOK OP OPTICAL GLASS PROPERTIES", 1986, ACADEMIC PRESS, ISBN: 0-12-078140-9, pages: 163,583 - 584
BRAMBILLA G ET AL: "Photorefractive index gratings in SnO/sub 2/:SiO/sub 2/ optical fibers", APPLIED PHYSICS LETTERS, 14 FEB. 2000, AIP, USA, vol. 76, no. 7, pages 807 - 809, XP002145427, ISSN: 0003-6951 *
BRAMBILLA G. ET AL., APPLIED PHYS. LETT., vol. 76, 2000, pages 807
DATABASE WPI Section Ch Week 199614, Derwent World Patents Index; Class G06, AN 1996-135983, XP002145428 *
DONG L. ET AL., IEEE PHOTONICS TECH. LETT., vol. 1048, 1995
DONG L. ET AL., OPTICS LETT., vol. 20, 1995, pages 1982
IMAMURA K. ET AL., ELECTRONICS LETT., vol. 34, 1998, pages 1772
O.V. MAZURIN ET AL.: "HANDBOOK OF GLASS DATA PART C TERNARY SILICATE GLASSES", 1968, ELSEVIER, ISBN: 0-444-42889-5, pages: 581,585, - 592,593,

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2850646A1 (fr) * 2003-02-03 2004-08-06 Schott Glas Corps photostructurable, procede pour le traitement d'un verre et/ou d'une vitroceramique, production de divers produits qui en sont derives, leur utilisation et objet utilisant ledit corps
CN112526671A (zh) * 2020-12-15 2021-03-19 新沂市锡沂高新材料产业技术研究院有限公司 一种低损耗的玻璃陶瓷平面光波导及其制备方法
CN112526671B (zh) * 2020-12-15 2022-03-11 新沂市锡沂高新材料产业技术研究院有限公司 一种低损耗的玻璃陶瓷平面光波导及其制备方法

Also Published As

Publication number Publication date
ATE286492T1 (de) 2005-01-15
EP1265820B1 (fr) 2005-01-05
DE60108228D1 (de) 2005-02-10
DE60108228T2 (de) 2005-12-08
EP1265820A1 (fr) 2002-12-18
AU4090801A (en) 2001-10-03

Similar Documents

Publication Publication Date Title
EP0823062B1 (fr) Dispositif pour guide d'ondes optique
Dianov et al. Germania-based core optical fibers
Dong et al. Enhanced photosensitivity in tin-codoped germanosilicate optical fibers
Brambilla et al. Photorefractive index gratings in SnO 2: SiO 2 optical fibers
EP0272258B1 (fr) Fabrication de fibres optiques
JP3386381B2 (ja) シリカベースの光ファイバを有する物品
EP0849231B1 (fr) Dispositif optique à guide d'onde codopé athermalisé
EP0810453A1 (fr) Dispositif comprenant une fibre optique microstructurée et méthode pour la fabrication d'une telle fibre
CA2443127A1 (fr) Guides d'ondes a fibre a indice de contraste eleve et applications
US6643442B2 (en) Optical waveguides and devices including same
US5279634A (en) Method of fabricating strip monomode active optical waveguides by vitrifying an interior portion of a tube with a laser
US20120324959A1 (en) High temperature stable fiber grating sensor and method for producing same
EP1265820B1 (fr) Guides d'ondes optiques et dispositifs incorporant lesdits guides d'ondes
Kasik et al. Glass materials for optical fibers
CN101698566A (zh) 一种同时具有紫外光致折射率变化和光放大特性的玻璃材料
YAMASAKI et al. Characteristics of long-period fiber grating utilizing periodic stress relaxation
Chen et al. Vacuum-ultraviolet laser-induced refractive-index change and birefringence in standard optical fibers
Shi et al. Correlation between glass viscosity and the high-temperature lifetime of silica fiber Bragg gratings directly written by a femtosecond laser
Brambilla et al. Enhanced photorefractivity in tin-doped silica optical fibers
EP3561559A1 (fr) Fibre optique avec profil de photosensibilité façonné pour produire des structures à modulation photo-induite de l'indice de réfraction, en particulier des réseaux de bragg
Kim et al. Suppression of cladding-mode coupling loss in fiber Bragg gratings by independent control of refractive index and photosensitive profiles in a single-mode optical fiber
Yang et al. Photo-induced refractive index change of bismuth-based silicate glass
Oh et al. Compositional dependence of the temperature sensitivity in a long period grating imprinted on GeO2-B2O3 co-doped core silica fibers
Kopp et al. Chiral fiber sensors
Reekie et al. Material considerations for Bragg fiber gratings

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
WWE Wipo information: entry into national phase

Ref document number: 2001911990

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 10241615

Country of ref document: US

WWP Wipo information: published in national office

Ref document number: 2001911990

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: JP

WWG Wipo information: grant in national office

Ref document number: 2001911990

Country of ref document: EP